1. Field of the Invention
The present invention relates to a battery authentication system capable of performing authentication between a portable device and a battery manufactured specifically for use in the portable device. The present invention further relates to a battery authentication system that performs authentication between a battery charger and a battery manufactured specifically for use in the battery charger. The present invention further relates to an electronic device, a battery, and a battery charger adapted to the battery authentication system.
2. Description of Related Art
Recently, many portable devices come with a battery authentication system. The battery authentication system performs authentication between a portable device and a battery manufactured specifically for use in the portable device. The battery authentication system is capable of regulating the use of a counterfeit battery in the portable device. Patent Document (JP 2005-151368 A) discloses an exemplary battery authentication system.
FIG. 10 is a block diagram showing a conventional battery authentication system. The battery authentication system performs authentication between an electronic device 100 and a genuine battery 101, a non-genuine battery 102, or a counterfeit battery 103.
The electronic device 100 includes an authentication IC 105, a control portion 106, and a power supply portion 107. The electronic device 100 is not limited particularly, as long as it can be operated by electric power supplied by a battery. The electronic device 100 is preferably a portable device such as a video camera, a digital camera, and a mobile phone terminal.
The authentication IC 105 executes authentication processing between the electronic device and the battery. Specifically, the authentication IC 105 requires the battery mounted on the electronic device 100 to provide its authentication information, compares the authentication information sent from the battery with authentication information stored in the authentication IC 105, and outputs a comparison result (authentication result) to the control portion 106.
The power supply portion 107 supplies electric power from the battery to respective portions in the electronic device 100.
The control portion 106 controls the operation of the power supply portion 107 based on the authentication result sent from the authentication IC 105. Specifically, when the battery is authenticated successfully in the authentication IC 105, the control portion 106 permits the operation of the power supply portion 107. On the other hand, when the battery is not authenticated in the authentication IC 105, the control portion 106 does not permit the operation of the power supply portion 107.
The genuine battery 101 is a battery manufactured by a manufacturer of the electronic device 100 (hereinafter, referred to as a device manufacturer), or a battery manufactured by a manufacturer (hereinafter, referred to as a genuine battery manufacturer) authorized by the device manufacturer to manufacture the battery. The genuine battery 101 is labeled with the same brand name as that given on the electronic device 100. The genuine battery 101 includes an authentication IC 104. The authentication IC 104 is an information device storing information for performing authentication between the authentication IC 104 and the paired authentication IC 105.
The non-genuine battery 102 is a battery authorized by the device manufacturer to be used in the electronic device 100. The non-genuine battery 102 is manufactured by a manufacturer (hereinafter, referred to as a non-genuine battery manufacturer) different from the device manufacturer and the genuine battery manufacturer, and is in circulation with an original brand name of the non-genuine battery manufacturer. The non-genuine battery 102 has substantially the same appearance, function, and performance as those of the genuine battery 101. The non-genuine battery 102 does not include an authentication IC as mounted on the genuine battery 101. The non-genuine battery 102 plays an effective role in ensuring the supply of batteries in areas that cannot be covered by the genuine battery 101 alone, and marketing a product with a battery capacity that is not commercially available for the genuine battery 101. The supply of the non-genuine battery 102 also helps promote the sales of electronic devices.
The counterfeit battery 103 is a battery manufactured by a manufacturer that is not authorized by the device manufacturer. Although the counterfeit battery 103 is similar in appearance to the genuine battery 101, it does not necessarily ensure sufficient performance and function because its internal structure is simplified for a price reduction. The counterfeit battery 103 includes no authentication IC.
Hereinafter, the operation of the conventional battery authentication system will be described.
When a battery is mounted in a predetermined battery mounting portion (not shown), and a power supply switch (not shown) is turned from off to on, the electronic device 100 starts authentication processing. Specifically, the authentication IC 105 requires the battery mounted in the battery mounting portion to provide its authentication information, and executes authentication processing based on the authentication information sent from the battery.
When the genuine battery 101 is mounted on the electronic device 100, the authentication IC 105 obtains the authentication information from the authentication IC 104 of the genuine battery 101, and compares it with authentication information stored in the authentication IC 105. The authentication IC 105 sends a result of the comparison to the control portion 106 as an authentication result. When the battery is authenticated successfully according to the authentication result, the control portion 106 activates the power supply portion 107. The power supply portion 107 supplies electric power to the respective portions in the electronic device 100, thereby activating the electronic device 100.
When the counterfeit battery 103 is mounted on the electronic device 100, the authentication IC 105 executes authentication processing. Since the counterfeit battery 103 includes no authentication IC, the counterfeit battery 103 is not authenticated. The control portion 106 regulates the activation of the power supply portion 107 based on an authentication result (unsuccessful authentication) sent from the authentication IC 105. Since the power supply portion 107 cannot supply electric power to the respective portions in the electronic device 100, the electronic device 100 cannot be operated.
When the non-genuine battery 102 is mounted on the electronic device 100, the authentication IC 105 executes authentication processing. Since the non-genuine battery 102 includes no authentication IC, the non-genuine battery 102 is not authenticated. The control portion 106 regulates the activation of the power supply portion 107 based on an authentication result (unsuccessful authentication) sent from the authentication IC 105. Since the power supply portion 107 cannot supply electric power to the respective portions in the electronic device 100, the electronic device 100 cannot be operated.
As described above, according to the conventional battery authentication system, it is impossible to perform authentication between the electronic device 100 and the non-genuine battery 102, so that the non-genuine battery 102 cannot be used in the electronic device 100.
The non-genuine battery 102 has the advantages of ensuring the supply of batteries in areas that cannot be covered by the genuine battery 101 alone, and marketing a product with a battery capacity that is not commercially available for the genuine battery 101. Further, the supply of the non-genuine battery 102 is also advantageous in helping promote the sales of electronic devices. However, the conventional battery authentication system cannot bring about the above-described advantages.